Yes, there are still a few inhibiting social settings where people must forgo that primal urge to pull out a cell phone and send a quick text message or two.

But those who can't bear such timeouts may soon have a way to keep communicating.

Researchers have created a prototype for a touch screen that can be used to send messages while it's concealed in a jacket or pants pocket. The stealthy screen works when it is touched through the fabric, whether it is silk, cotton or even thick fleece.

In classes or meetings of the future, with your hands tucked beneath the conference table or desk, you may rest a fingertip discreetly on the pocket that holds the touch screen and handle a call by tracing a message like "Running late. In a mtg" on the fabric above the hidden screen. The touch screen will understand the message - it has a program to decipher handwriting, even of the scrawling sort.

So while you're writing on your pocket, you can maintain polite eye contact with the group, no longer betrayed by those telltale downward gazes necessary to text with a standard screen. (Unfortunately, you will still need to look down, and be possessed of X-ray vision, to view any response.)

The prototype uses sensors similar to those in most touch screens and is mounted on the back of a smart-phone case.

"There are a lot of situations where this technology could be useful," said Jeffrey Bigham, an assistant professor in the computer science department at the University of Rochester, who chaired a conference panel on computer user interfaces where PocketTouch was demonstrated.

"It's a way to send short messages when it is not socially appropriate to fish out your device," he said, or in many other instances when people simply don't want to go to the trouble of removing a device from a pocket.

Touch screens usually do not work through fabric, as people who must pull off their gloves to text on winter days well know. But PocketTouch uses software that can interpret signals through cloth.

"Most touch screens are calibrated in a static way, only responding to direct touch with a finger, and rejecting a slightly different signal," Benko said.

PocketTouch, by contrast, calibrates continuously, adapting to different kinds of fabrics.

Saponas said the system could understand long messages like, "The quick brown fox jumped over the lazy dog" when written word by word on the screen. But he sees the strength of the technology in its ability to send short messages.

"We wanted a way for people to be able to respond quickly," he said, without having to break eye contact with a group.

"We're not trying to replace the functionality of the touch screen to compose e-mail and browse the Web," Saponas said.

Rather, he added, the goal is to lower the barrier to minimal communication.

PocketTouch is among several unusual approaches that its inventors have explored for computer user interfaces, said Krzysztof Gajos, an assistant professor of computer science at Harvard.

Among Saponas' projects is a dental retainer embedded with infrared optical sensors that use tongue movements to control electronic devices. A quadriplegic user, for example, might thus be able to control a computer, cell phone or television.